Programa Javascript para rotar la lista enlazada en bloque

Javascript

<script>
// JavaScript program to rotate a
// linked list block wise 
  
// Link list node 
class Node 
{
    constructor() 
   {
        this.data = 0;
        this.next = null;
    }
}
  
var tail;
  
// Recursive function to rotate one block
function rotateHelper(blockHead,  
                      blockTail, d, k)
{
    if (d == 0)
        return blockHead;
  
    // Rotate Clockwise
    if (d > 0) 
    {
        var temp = blockHead;
        for (i = 1; temp.next.next != null &&
             i < k - 1; i++)
            temp = temp.next;
        blockTail.next = blockHead;
        tail = temp;
        return rotateHelper(blockTail, 
        temp, d - 1, k);
    }
  
    // Rotate anti-Clockwise
    if (d < 0) 
    {
        blockTail.next = blockHead;
        tail = blockHead;
        return rotateHelper(blockHead.next, 
        blockHead, d + 1, k);
    }
    return blockHead;
}
  
// Function to rotate the linked list 
// block-wise
function rotateByBlocks(head, k, d) 
{
    // If length is 0 or 1 return head
    if (head == null || head.next == null)
        return head;
  
    // if degree of rotation is 0, 
    // return head
    if (d == 0)
        return head;
  
    var temp = head;
    tail = null;
  
    // Traverse upto last element of 
    // this block
    var i;
    for (i = 1; temp.next != null && 
         i < k; i++)
        temp = temp.next;
  
    // Storing the first node of next block
    var nextBlock = temp.next;
  
    // If nodes of this block are less than k.
    // Rotate this block also
    if (i < k)
        head = rotateHelper(head, temp,
                            d % k, i);
    else
        head = rotateHelper(head, temp, 
                            d % k, k);
  
    // Append the new head of next block to
    // the tail of this block
    tail.next = rotateByBlocks(nextBlock, 
                               k, d % k);
  
    // return head of updated Linked List
    return head;
}
  
// UTILITY FUNCTIONS
// Function to push a node 
function push(head_ref, new_data) 
{
    var new_node = new Node();
    new_node.data = new_data;
    new_node.next = head_ref;
    head_ref = new_node;
    return head_ref;
}
  
// Function to print linked list 
function printList(node) 
{
    while (node != null) 
    {
        document.write(node.data + " ");
        node = node.next;
    }
}
  
// Driver code 
// Start with the empty list 
var head = null;
  
// Create a list 1.2.3.4.5.
// 6.7.8.9.null
for (i = 9; i > 0; i -= 1)
    head = push(head, i);
document.write("Given linked list <br/>");
printList(head);
  
// k is block size and d is number of
w// rotations in every block.
var k = 3, d = 2;
head = rotateByBlocks(head, k, d);
document.write(
"<br/>Rotated by blocks Linked list <br/>");
printList(head);
// This code is contributed by gauravrajput1 
</script>